diff options
Diffstat (limited to 'third_party/libwebrtc/media/base/video_broadcaster.cc')
-rw-r--r-- | third_party/libwebrtc/media/base/video_broadcaster.cc | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/third_party/libwebrtc/media/base/video_broadcaster.cc b/third_party/libwebrtc/media/base/video_broadcaster.cc new file mode 100644 index 0000000000..43c17734e3 --- /dev/null +++ b/third_party/libwebrtc/media/base/video_broadcaster.cc @@ -0,0 +1,214 @@ +/* + * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +#include "media/base/video_broadcaster.h" + +#include <algorithm> +#include <vector> + +#include "absl/types/optional.h" +#include "api/video/i420_buffer.h" +#include "api/video/video_rotation.h" +#include "media/base/video_common.h" +#include "rtc_base/checks.h" +#include "rtc_base/logging.h" + +namespace rtc { + +VideoBroadcaster::VideoBroadcaster() = default; +VideoBroadcaster::~VideoBroadcaster() = default; + +void VideoBroadcaster::AddOrUpdateSink( + VideoSinkInterface<webrtc::VideoFrame>* sink, + const VideoSinkWants& wants) { + RTC_DCHECK(sink != nullptr); + webrtc::MutexLock lock(&sinks_and_wants_lock_); + if (!FindSinkPair(sink)) { + // `Sink` is a new sink, which didn't receive previous frame. + previous_frame_sent_to_all_sinks_ = false; + + if (last_constraints_.has_value()) { + RTC_LOG(LS_INFO) << __func__ << " forwarding stored constraints min_fps " + << last_constraints_->min_fps.value_or(-1) << " max_fps " + << last_constraints_->max_fps.value_or(-1); + sink->OnConstraintsChanged(*last_constraints_); + } + } + VideoSourceBase::AddOrUpdateSink(sink, wants); + UpdateWants(); +} + +void VideoBroadcaster::RemoveSink( + VideoSinkInterface<webrtc::VideoFrame>* sink) { + RTC_DCHECK(sink != nullptr); + webrtc::MutexLock lock(&sinks_and_wants_lock_); + VideoSourceBase::RemoveSink(sink); + UpdateWants(); +} + +bool VideoBroadcaster::frame_wanted() const { + webrtc::MutexLock lock(&sinks_and_wants_lock_); + return !sink_pairs().empty(); +} + +VideoSinkWants VideoBroadcaster::wants() const { + webrtc::MutexLock lock(&sinks_and_wants_lock_); + return current_wants_; +} + +void VideoBroadcaster::OnFrame(const webrtc::VideoFrame& frame) { + webrtc::MutexLock lock(&sinks_and_wants_lock_); + bool current_frame_was_discarded = false; + for (auto& sink_pair : sink_pairs()) { + if (sink_pair.wants.rotation_applied && + frame.rotation() != webrtc::kVideoRotation_0) { + // Calls to OnFrame are not synchronized with changes to the sink wants. + // When rotation_applied is set to true, one or a few frames may get here + // with rotation still pending. Protect sinks that don't expect any + // pending rotation. + RTC_LOG(LS_VERBOSE) << "Discarding frame with unexpected rotation."; + sink_pair.sink->OnDiscardedFrame(); + current_frame_was_discarded = true; + continue; + } + if (sink_pair.wants.black_frames) { + webrtc::VideoFrame black_frame = + webrtc::VideoFrame::Builder() + .set_video_frame_buffer( + GetBlackFrameBuffer(frame.width(), frame.height())) + .set_rotation(frame.rotation()) + .set_timestamp_us(frame.timestamp_us()) + .set_id(frame.id()) + .build(); + sink_pair.sink->OnFrame(black_frame); + } else if (!previous_frame_sent_to_all_sinks_ && frame.has_update_rect()) { + // Since last frame was not sent to some sinks, no reliable update + // information is available, so we need to clear the update rect. + webrtc::VideoFrame copy = frame; + copy.clear_update_rect(); + sink_pair.sink->OnFrame(copy); + } else { + sink_pair.sink->OnFrame(frame); + } + } + previous_frame_sent_to_all_sinks_ = !current_frame_was_discarded; +} + +void VideoBroadcaster::OnDiscardedFrame() { + webrtc::MutexLock lock(&sinks_and_wants_lock_); + for (auto& sink_pair : sink_pairs()) { + sink_pair.sink->OnDiscardedFrame(); + } +} + +void VideoBroadcaster::ProcessConstraints( + const webrtc::VideoTrackSourceConstraints& constraints) { + webrtc::MutexLock lock(&sinks_and_wants_lock_); + RTC_LOG(LS_INFO) << __func__ << " min_fps " + << constraints.min_fps.value_or(-1) << " max_fps " + << constraints.max_fps.value_or(-1) << " broadcasting to " + << sink_pairs().size() << " sinks."; + last_constraints_ = constraints; + for (auto& sink_pair : sink_pairs()) + sink_pair.sink->OnConstraintsChanged(constraints); +} + +void VideoBroadcaster::UpdateWants() { + VideoSinkWants wants; + wants.rotation_applied = false; + wants.resolution_alignment = 1; + wants.aggregates.emplace(VideoSinkWants::Aggregates()); + wants.is_active = false; + + // TODO(webrtc:14451) : I think it makes sense to always + // "ignore" encoders that are not active. But that would + // probably require a controlled roll out with a field trials? + // To play it safe, only ignore inactive encoders is there is an + // active encoder using the new api (requested_resolution), + // this means that there is only a behavioural change when using new + // api. + bool ignore_inactive_encoders_old_api = false; + for (auto& sink : sink_pairs()) { + if (sink.wants.is_active && sink.wants.requested_resolution.has_value()) { + ignore_inactive_encoders_old_api = true; + break; + } + } + + for (auto& sink : sink_pairs()) { + if (!sink.wants.is_active && + (sink.wants.requested_resolution || ignore_inactive_encoders_old_api)) { + continue; + } + // wants.rotation_applied == ANY(sink.wants.rotation_applied) + if (sink.wants.rotation_applied) { + wants.rotation_applied = true; + } + // wants.max_pixel_count == MIN(sink.wants.max_pixel_count) + if (sink.wants.max_pixel_count < wants.max_pixel_count) { + wants.max_pixel_count = sink.wants.max_pixel_count; + } + // Select the minimum requested target_pixel_count, if any, of all sinks so + // that we don't over utilize the resources for any one. + // TODO(sprang): Consider using the median instead, since the limit can be + // expressed by max_pixel_count. + if (sink.wants.target_pixel_count && + (!wants.target_pixel_count || + (*sink.wants.target_pixel_count < *wants.target_pixel_count))) { + wants.target_pixel_count = sink.wants.target_pixel_count; + } + // Select the minimum for the requested max framerates. + if (sink.wants.max_framerate_fps < wants.max_framerate_fps) { + wants.max_framerate_fps = sink.wants.max_framerate_fps; + } + wants.resolution_alignment = cricket::LeastCommonMultiple( + wants.resolution_alignment, sink.wants.resolution_alignment); + + // Pick MAX(requested_resolution) since the actual can be downscaled + // in encoder instead. + if (sink.wants.requested_resolution) { + if (!wants.requested_resolution) { + wants.requested_resolution = sink.wants.requested_resolution; + } else { + wants.requested_resolution->width = + std::max(wants.requested_resolution->width, + sink.wants.requested_resolution->width); + wants.requested_resolution->height = + std::max(wants.requested_resolution->height, + sink.wants.requested_resolution->height); + } + } else if (sink.wants.is_active) { + wants.aggregates->any_active_without_requested_resolution = true; + } + + wants.is_active |= sink.wants.is_active; + } + + if (wants.target_pixel_count && + *wants.target_pixel_count >= wants.max_pixel_count) { + wants.target_pixel_count.emplace(wants.max_pixel_count); + } + current_wants_ = wants; +} + +const rtc::scoped_refptr<webrtc::VideoFrameBuffer>& +VideoBroadcaster::GetBlackFrameBuffer(int width, int height) { + if (!black_frame_buffer_ || black_frame_buffer_->width() != width || + black_frame_buffer_->height() != height) { + rtc::scoped_refptr<webrtc::I420Buffer> buffer = + webrtc::I420Buffer::Create(width, height); + webrtc::I420Buffer::SetBlack(buffer.get()); + black_frame_buffer_ = buffer; + } + + return black_frame_buffer_; +} + +} // namespace rtc |